The present invention relates to the field of sports boots. It relates in particular to a sports boot, the upper of which comprises two elements assembled by adhesive bonding and a mechanical means or by adhesive bonding and stitching.
In order to produce increasingly comfortable ski boots, to make them use is made of materials with different characteristics, particularly different stiffness characteristics. This therefore poses the problem of assembling these elements that consist of different materials. To produce certain boots, bi-injection-moulding processes are employed, which makes it possible to construct shells with zones of different stiffness.
Furthermore, U.S. Pat. No. 3,483,638, the content of which is incorporated by reference, discloses a process for manufacturing ski boots in which two flaps arranged over the top of the upper partially cover over one another and have buckles and tensioning devices, respectively. The manufacturing process consists in the boot vamp being open, in the buckles and tensioning devices being, respectively, fastened over each of the flaps, and then in the flaps, which are preferably made from an elastic plastics material, being attached to the edges of the vamp by stitching, for example.
U.S. Pat. No. 6,148,546, the content of which is incorporated by reference, discloses a sports boot that includes a sole from which an upper that covers the foot extends. The upper is composed of two parts. The first part is produced in a relatively rigid material, constituting a cradle forming a rear casing for housing the user""s heel and in a single piece with the sole in the heel zone. The second part of the upper is produced in a relatively flexible material, constituting a band for covering over the front of the user""s foot and for attaching securely to the front part of the sole on the one hand and to the edges of the rear casing. The patent describes, as linking means between the band and the sole, rivets, adhesive bonding, welding or, alternatively, stitching.
However, these processes present drawbacks in that the assembly methods that use adhesive bonding are relatively poorly resistant to mechanical stresses. They are particularly sensitive when the adhesive-bonding joint undergoes peeling stresses, i.e. when tensile stresses are applied to it. Assembly methods using rivets are not watertight and are unattractive. Assembly methods using welding and assembly methods using stitching cannot be applied to all the materials. Assembly methods using stitching are neither attractive nor watertight.
The object of the invention is to produce a sports boot that has an assembly that mitigates these drawbacks. In particular, the invention proposes producing a boot that has two elements linked by a strong, leaktight, and attractive assembly method. The assembly method must also allow the linking of materials of different types.
The sports boot according to the invention is noteworthy in that a part of one of the elements of the upper permanently covers over the assembly.
According to one embodiment, one of the elements covers over the assembly by folding over on itself.
In this case, the element covering over the assembly may be adhesively bonded onto itself.
The assembly process that makes it possible to obtain such a boot is noteworthy in that it comprises the stages:
assembling the two elements by adhesive bonding and a mechanical means or by adhesive bonding and stitching;
folding one of the elements over itself in order to cover over the assembly.
According to one embodiment, a lip on the first element covers over the assembly and is adhesively bonded onto the second element.
The assembly process that makes it possible to obtain such a boot is noteworthy in that it comprises the following stages:
assembling the two elements by a mechanical means or by stitching;
covering over the assembly with a lip on the first element;
adhesively bonding the lip to the second element.
According to the embodiments, the two elements are a shell and a flap.
According to the embodiments, the first element is a shell and the second is a flap.
According to the embodiments, the first element is a flap and the second is a shell.